Huajing,
I don't normally edit my photos.. too time consuming.. those I take with my camera, I just print as it is, unless i want to fit many into one 4R, then I do the layout. This time round I edit colour/lighting because these are studio pics.. so I wanted them to come out nicer.
There are too many factors for colour/lighting.. it also depends on your computer screen colour. But argar-argar can tell.. I mostly make the pics brighter, colour I only adjust a little bit, not much.. because for studio pics, they normally turn out warm and colour saturation is ok. Certain brands of camera will give your photos a bluish tint (cool) or yellowish tint (warm).. depends on what you like too.
Anyway, it's too technical to explain in details and I am not a true expert. Now a days, the digital cameras are all very advanced, so the colour usually will turn out alright. Also, it depends on which photo-lab u send for printing. I am quite particular about my prints and I won't send to those neighbourhood shops (unless I know their quality is good).
Ok.. this is really too technical.. If u don't understand what I mean, it's ok. Don't have to worry too much. Most of the time the prints should turn out fine.